analyses. Complexes derived from weakly coordinating phosphine oxides have eluded isolation due to loss of phosphine oxide and formation of barely soluble multinuclear palladium complexes 1n by bridging coordination of the sulfonate group to various Pd centers. Hence, the (P∧O)PdMe fragment 1 exhibits an intrinsic limitation with respect to coordination of weak donors. Species 1 generated in situ in the
                                    各种膦氧化物的协调强度OPR 3朝向的烯烃聚合催化剂(P ∧ O)P
DME(P ∧ O =κ 2 - P,O -Ar 2 P c ^ 6 ħ 4 SO 2 ö用Ar = 2- MeOC 6 ħ 4)与
DMso相比已经确定。反应1-
DMso + L⇆1 -L + 
DMso的平衡常数K L范围从3.5(对于富电子的OPBu 3)到10 –3(对于电子贫乏的OP(p -CF 3)C 6 H 4)3。络合物从更强配位的膦氧化物衍生的,即,[(P ∧ O)P
DME(L)](1-L为:L = OPBu 3,OPOct 3,
OPPh 3)已被分离和完全表征。另外,通过X射线衍射分析来分析1-OPBu 3和1-
OPPh 3。由于膦氧化物的损失以及通过将
磺酸盐基团的配位桥接到各个Pd中心上而形成的几乎不溶的多核
钯配合物1 n,衍生自弱配位的氧化膦的配合物无法进行分离。因此,(P∧ O)P
DME片段1所表现出